This particular error message can mean a whole range of different issues, which is why I always ask people to send their log files. If you want to look at most of the known solutions yourself, there is a topic over at the Steam forums: http://steamcommunity.com/app/296970/di ... 040092698/

Of course, do feel free to send your log file to our suport mail, I'd be glad to (try to) help :)